Parallel Connection of 1200 V/100 A SiC MOSFET Half-bridge Modules

Abstract

Silicon (Si) insulated-gate bipolar transistors (IGBTs) are widely used in power converters. Silicon carbide (SiC) technology will push the limits of switching devices in three directions: higher blocking voltage, higher operating temperature, and higher switching speed. The first SiC-metal-oxide-semiconductor field-effect transistor (MOSFET) half-bridge modules (SiC HBM) are now commercially available and look promising. Although they are still limited in breakdown voltage, these components should, for instance, improve traction-chain efficiencies. In particular, a significant reduction in switching losses is to be expected which should lead to improvements in power-to-weight ratios-of particular interest for rolling-stock. Nevertheless, because of the high switching speed and the high current levels required by traction applications, the implementation of these modules is critical. In this paper, the authors investigate the parallel connection of SiC HBM with a focus on traction equipment. The key points are underlined and an original approach is proposed to design the bus-bar and the gate-drive circuit. Experimental results performed on an opposition method test bench, valid the correct operation of three SiC modules in parallel.